The invention relates to a method for producing a multicomponent cartridge that serves to separately store and coextrude at least two components of a flowable composition, in which the multicomponent cartridge has a cylinder with at least two chambers, separate from one another, for separate storage of the components of the composition. The invention further relates to a multicomponent cartridge for separate storage and coextrusion of at least two components of a flowable composition, having a cylinder for receiving the composition, having an extrusion piston for extruding the composition, and having at least one outlet opening for the composition, the components of the composition being stored separately from one another in at least two chambers of the cylinder that extend in the longitudinal direction of the cylinder of the multicomponent cartridge. The term flowable composition should be understood in particular to mean a pastelike material with pastelike components, such as multicomponent adhesives, multicomponent synthetic resins, or multicomponent mortars.
Cartridges are used for injecting adhesives or sealants and are inserted for this purpose into cartridge presses. For storage and extrusion of two-component composition, cartridges are used that have a cylinder subdivided into two chambers, in which the two components are introduced and stored separately from one another. By means of one or two extrusion pistons, the components located in the chambers can be coextruded, in a predetermined mixture ratio, through the outlet opening. The extruded components are mixed with one another in a static mixer mounted at the outlet opening.
From German Patent Disclosure DE 39 13 409 A1, a two-component cartridge is known which has the shape and construction of an one-component cartridge and can thus be used in conventional cartridge presses for one-component cartridges. For embodiment as a two-component cartridge, one cylinder of the known cartridge is split into two chambers, located side by side, by a flexible partition located in the longitudinal direction and joined by material-locking to the cylinder wall and cartridge wall. Upon extrusion of the components by the extrusion piston, the flexible partition is successively disconnected from the cylinder and cartridge walls and received in a hollow chamber in the extrusion piston.
In German Patent Disclosure DE 102 07 763 A1, a two-component cartridge is disclosed that has two tubular containers separate from one another that extend over sectors of a circle and add up to a full circle, so that the cartridge is in cylindrical form. For the extrusion, the containers are put together and placed in a cylinder of a cartridge press and pressed together in the longitudinal direction by an extrusion piston of the cartridge press.
For long-term storage of as yet unused cartridges, it is necessary that the components be protected against environment factors. This is accomplished as a rule by placing the components in plastic cylinders, whose fill openings and outlet openings are sealingly closed. Conventional cartridges are preferably made from polyolefin plastics. They have only limited barrier properties against diffusion of water into or out of the cartridge, which is either inadequate for hybrid motors or PU systems or requires a thick cartridge wall in order to reduce the water vapor diffusion down to a tolerable amount. In such compositions, the water vapor diffusion plays a decisive role in the durability of the components of the composition that are stored in the cartridge, since one of the components reacts with water, making the composition unusable.